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Silver smoky black determined by the Silver gene plus one Cream Dilution gene appears, on the outside, to be very similar to ordinary silver black with a little more yellowish or brownish shade to the body (Photosssss1 &ssss1). Unfortunately, it isn’t always possible to measure this difference by the eye.
There are additional rare combinations, such as silver dun buckskin, which can occur in the Icelandic breed. The horse is a light, sandy color, the lower part of the legs is light ashy, and sandy-colored hair is mixed with black and ashy in the mane and tail. Primitive markings are brown.
Inheritance of Colors Determined by the Silver Gene
The Silver gene mutation is dominant, located on the sixth chromosome, and the gene is named PMEL17 (pre-melanosomal protein 17). Two dominant alleles of this gene responsible for silver colors are designated “Z,” and the recessive allele that doesn’t influence color has the symbol “z.” There is a DNA test for two dominant Silver mutations.
The action of the gene on pigment is most noticeable on guard hair and to a lesser extent on the body hair. As mentioned already, it does not affect the color of a red horse. The effect of the Silver gene on horse colors is presented in the table below: